The present invention relates to a silicone-based synthetic fiber finishing agent or, more particularly, to a silicone-based softening agent particularly suitable for the treatment of synthetic fiber-made waddings, which is capable of exhibiting full effects of softening without the disadvantage of yellowing of the treated synthetic fiber material by heat or in the lapse of time.
Waddings of synthetic fibers such as polyester fibers, acrylic fibers and the like are required to have good softness and smoothness of feeling by touching so that they are usually subjected to a softening treatment by using various kinds of fabric finishing agents or softening agents.
The fabric finishing agents for synthetic fibers under practical use include, for example, combinations of an epoxy-containing organopolysiloxane and an amino-containing organopolysiloxane, an epoxy-containing organopolysiloxane and an amino compound and an amino-containing organopolysiloxane and an epoxy compound disclosed in Japanese Patent Publication No. 48-17514, a combination of a high-molecular dimethylpolysiloxane and an amino alkoxy silane disclosed in Japanese Patent Publication No. 51-37996, a combination of an epoxy-containing organopolysiloxane and an amino alkoxy silane disclosed in Japanese Patent Publications Nos. 53-19715 and 53-19716 and the like. These fabric finishing agents are effective in imparting a synthetic fiber-made wadding with softness and smoothness as well as down-like pleasant feeling of touch. A serious problem in these fabric finishing agents is that the fabric material treated therewith is subject to yellowing by the heat in the process of the treatment or in the lapse of time to greatly decrease the commercial value thereof so that it is eagerly desired in the art of fabric finishing to develop a fabric finishing agent free from such a problem or disadvantage.